AgentsMakingFriends

Enable OpenClaw Agent to communicate with other AI Agents using the A2A (Agent2Agent) protocol. Use when: (1) User wants to connect two OpenClaw instances ac...

A2A Protocol

Enable OpenClaw Agent to communicate with other AI Agents using the A2A (Agent2Agent) protocol - an open standard by Google for inter-agent communication.

Quick Start

Calling a Remote Agent (Client Mode)

python ~/.openclaw/workspace/skills/a2a-protocol/scripts/a2a_client.py \
  "http://remote-agent:8080/a2a" \
  "Hello, please help me with this task" \
  "your-bearer-token"

Exposing as A2A Service (Server Mode)

python ~/.openclaw/workspace/skills/a2a-protocol/scripts/a2a_server.py --port 8080

Core Concepts

Concept	Description
Agent Card	JSON document describing agent identity, capabilities, endpoint
Task	Unit of work with lifecycle (pending → running → completed)
Message	Communication turn with role and parts
Part	Smallest content unit (text/file/data)
Artifact	Output generated by agent

Workflow

1. Agent A (Client)          2. Agent B (Server)
   │                              │
   │ GET /.well-known/agent.json │
   │─────────────────────────────►│
   │       Agent Card             │
   │◄─────────────────────────────│
   │                              │
   │ POST /rpc (message/send)     │
   │─────────────────────────────►│
   │                              │
   │      Task Response           │
   │◄─────────────────────────────│

Configuration

Add remote agent info to TOOLS.md:

### A2A Agents

- Remote Agent Name:
  URL: http://1.2.3.4:8080/a2a
  Token: your-bearer-token

Resources

scripts/

• a2a_client.py - A2A client for calling remote agents
• a2a_server.py - A2A server for exposing OpenClaw as a service
• agent_card.json - Agent Card template

references/

• a2a-api.md - Complete A2A API reference

Troubleshooting

Connection Failed

1. Check network reachability (ping/telnet)
2. Verify firewall allows the port
3. Confirm token is correct

Agent Card Not Found

1. Ensure remote agent's A2A server is running
2. Check URL includes correct path